EP0028577B1 - Device for controlling a system for drawing strands of fibres - Google Patents

Description

The present invention relates to an improved device for drawing a wick of fibers with a view to converting it into a yarn.

It relates more particularly to a system for clutching and disengaging stretching sleeved trains, as well as to the application of such a device, in particular on machines for obtaining self-twisted yarns.

Until recently, the spinning looms fitted with wick drawing trains did not include a system allowing each position to be disengaged in the event of the food wick breaking.

Consequently, the risks of winding fibers around the rotary cylinders were very high and moreover the recovery operation was relatively delicate to perform.

With the emergence of the so-called "free fiber" spinning technique, and in particular the fact that this technique makes it possible to significantly increase production speeds, systems have been proposed which allow the individual clutching and disengaging of stretcher members, as described, for example, in US-A-3,327,464.

The solutions provided to solve this problem however do not give complete satisfaction and have a certain number of drawbacks in particular by the fact that, when relaunching, the clutch is done suddenly, which, given the high speeds of production, sometimes leads to breakage of the wick. Machines are also known for making self-twisted yarns and in particular self-twisted yarns of which at least one of the constituents has a core in its central part (patent from the United States of North America 4,033,102).

In general, these machines comprise, for each working position, a drawing device making it possible to simultaneously treat two wicks, a core being incorporated in at least one of the wicks upstream of the last pair of stretching cylinders.

On such machines, it is therefore essential that the wicking system is equipped with means allowing its automatic disengagement in the event of breakage, because, due to the presence of the core, the wire continues to be produced. Furthermore, these systems must be able to be adapted to automatically control the cutting of the core threads and stop the winding operation or, conversely, be able to be controlled by the breakage detectors, either of the core or of the wire formed.

The device according to the invention makes it possible to fulfill these objectives.

Furthermore, it also allows progressive engagement of the drill bit and jogging, which is particularly advantageous during the recovery operation. Finally, it can be easily adapted to deliver intermittently, or at variable speed, the treated material, in particular with a view to obtaining wires having effects (flame, etc.) over their length.

In general, the invention therefore relates to a device for controlling a drawing system of at least one wick of fibers with a view to its transformation into a yarn, said drawing system being of the type comprising a pair of supply cylinders, a double sleeve system and a pair of stretching cylinders, these elements being kept under pressure in normal operation by means of a pendulum arm which can be moved between an out of working position and a working position, this arm supporting the one of the supply cylinders, sleeves and stretching cylinders, clutch and disengage means being provided for each stretching system of the machine and it is characterized in that the drive of the food cylinders is obtained, at least during the launching operation, by means of a clutch roller associated with each working position, said roller being movable and coming when it is in the engaged position, in contact with both one cylinders s food and with a drive shaft which extends over the entire length of the loom parallel and spaced from the driven food cylinder.

In the device according to the invention, the drive of the pair of stretching cylinders is carried out in a conventional manner, one of these cylinders being constituted by a splined drive shaft common to all the working positions, the shaft on which is supported the stretching cylinder carried by the pendulum arm.

The clutch roller associated with each working position will be made from a material allowing a friction drive, such as for example based on the material sold under the brand VULKOLAN.

Advantageously, the sleeves with which the stretching system is provided will be driven directly by the motor food cylinder, for example by means of a belt connecting said cylinder to the support shaft of one of the sleeves.

The displacement of the clutch roller according to the invention will be obtained by any suitable means such as for example by a lever system.

In one embodiment of the invention, the clutch and declutching device is associated with means allowing the automatic disengagement of the roller, these means being able to be controlled either by a breakage detector or by other members. safety devices, such as product wire break detectors.

In a variant of the invention, the clutch system comprises, as said previously, a roller associated with each working position, said roller being able to be brought during the launching operation into the engaged position by contact with both the one of the cylinders food and with a motor shaft extending over the entire length of the loom and being mounted on a support allowing, in normal operation, to bring it back to the disengaged position and which, simultaneously, replaces this friction drive means a member positive drive, such as for example a pinion which meshes with a corresponding pinion carried by the motor shaft. Finally, the device according to the invention can possibly be associated with means allowing an intermittent clutching of the roller with the driving cylinder so as to vary the flow rate of the wick treated.

• la figure 1 est une vue en perspective schématique de l'ensemble d'un dispositif conforme à l'invention,
• les figures 2 et 3 sont respectivement des vues de côté et de face d'une position de travail d'une machine d'autotorsion équipée d'un dispositif d'étirage de mèches conforme à l'invention,
• la figure 4 illustre une variante du dispositif d'embrayage conforme à l'invention permettant d'obtenir un embrayage progressif lors de l'opération de lancement et un embrayage positif en marche normale.
• La figure 1 illustre un système d'étirage à double manchons équipé d'un dispositif d'embrayage et de débrayage conforme à l'invention.

The invention and the advantages which it brings will however be better understood thanks to the example of embodiment given below by way of non-limiting illustration and which is illustrated by the attached diagrams in which:

• FIG. 1 is a schematic perspective view of the assembly of a device according to the invention,
• FIGS. 2 and 3 are respectively side and front views of a working position of a self-twisting machine equipped with a wicking device according to the invention,
• FIG. 4 illustrates a variant of the clutch device according to the invention making it possible to obtain a progressive clutch during the launching operation and a positive clutch in normal operation.
• Figure 1 illustrates a double sleeve stretching system equipped with a clutch and declutching device according to the invention.

This drawing system essentially comprises a pair of supply rollers 1, 2, a double sleeve system 3, 4 and a pair of drawing rollers 6, 7. The wick 8 comes from a supply source which is not shown and after stretching can receive any conventional treatment.

A pendulum arm 9 supports the cylinder 1, the sleeve 3, the cylinder 6 and is pivotally mounted on a fixed shaft 10, extending over the entire length of the loom, and on which are mounted a plurality of working positions.

In general, the pendulum arm 9 supports two sets of wick processing arranged symmetrically on either side of said arm. In Figure 1, only one drawing assembly has been shown.

Furthermore, in known manner, a core 11 can be introduced into the wick immediately before its passage through the pair of stretching cylinders 6, 7.

This assembly can be arranged either horizontally as shown in Figure 1, or vertically or at an angle.

A conventional pressure system makes it possible to maintain the elements 1, 3, 6 under a determined pressure with a grooved supply cylinder 2, a sleeve 4 and a grooved stretch cylinder 7.

The feed cylinder 2 is individual for each working position, while the cylinder 7 is constituted by a shaft common to all the positions extending over the entire length of the loom.

The cylinder 2 controls, for example by means of a belt 13, the drive of the shaft 14 carrying the sleeve 4.

A drive shaft 12, arranged parallel to the cylinder 2 and spaced therefrom extends over the entire length of the loom.

The engagement and disengagement of a stretching system are carried out, in accordance with the invention, by means of a drive roller 15, for example a VULKOLAN roller, which, by means of a system levers can be brought either into contact with cylinders 1 and 2 (engaged position), or out of contact with these (disengaged position).

In this embodiment, the movement of the roller 15 is controlled as follows. This roller is mounted on an axis 16 which slides in slides 17, 18 carried by the frame 20 of the loom. This axis 16 is integral with a rod 21, one end 22 of which is subjected to the action of a traction spring 23 holding the roller 15 out of contact with the shaft 12 and the cylinder 2.

The other end 24 of the rod 21 is subjected to the action of a spring 25 which bears on the rear face of a lever 26 articulated on an axis 27 extending over the entire length of the loom.

The other end 28 of the lever 26 is subjected to the action of a lever 29 mounted eccentrically on a disc 30 which can pivot around an axis 31 and take two positions A, B, one A corresponding to the position disengaged from the roller 15, the other B in the engaged position. The engaged position has simply been partially diagrammed by the dotted representation of the lever 29. The pivoting of this lever 29 can be obtained either manually by action on a handle 32 provided at the periphery of the disc 30, or by action of a jack 33 the rod of which rests on the lever 29 and the action of which is triggered in the event of an accident, such as a broken lock.

The operation of such a stretching device is as follows. In the disengaged position (shown in solid lines in Figure 1) the roller 15 is kept out of contact with the drive shaft 12 and the cylinder 2 under the action of the return spring 23, while, in the engaged position, the position shown in dotted lines, the end of the lever 29 comes at B, which causes the lever 26 to tilt and, consequently, the roller 15 against the motor shaft 12 and the cylinder 2 under the action of the spring 25.

During a breakage, a detector not shown, controls the actuation of the jack 33 by means of a solenoid valve, the rod of the jack pushing the lever 29 into position A and allowing the roller 15 to be returned under the action of the spring 23.

When restarting, it suffices to act on the lever 32 to cause the clutch by bringing the roller 15 into contact with the motor shaft 12 and the cylinder 2. This can be done gradually, or even intermittently, which favors the operation to revive the wick 8.

In the variant illustrated in FIG. 4, the roller 15 is controlled in the same manner as above during the restarting operation. However, in this variant, the roller is mounted on a support 34 arranged in such a way that, in normal operation, it is possible to disengage said roller 15 and simultaneously cause the drive of the shaft 12 by means of a pinion. 135 allowing a positive training. for this, one can use an assembly consisting of a cam 136 whose rotation can be controlled manually by means of a lever 137, this cam supporting on the one hand, the support 34 of the roller 15 and, on the other hand, a support 138 for the pinion 135. When the start-up is carried out, it is sufficient by simple action on the lever 137 to cause the pivoting of the cam 136 which causes the withdrawal of the roller 15 and simultaneously causes the clutch of the pinion 135 with a corresponding pinion 139 carried by the control shaft 12.

Such devices, whether the one illustrated in FIG. 1 or the variant illustrated in FIG. 4, are particularly suitable, but this is not limiting, for the production of self-twisted threads in which a core is incorporated into at least 1 'one of the wicks during its formation.

Figures 2 and 3 illustrate such an application.

In these figures, only the main elements of the device previously described and which is illustrated in Figure 1 have been shown. These elements are the food cylinders 1, 2, the double sleeve drawing system 3, 4, the drawing train 6, 7, the pendulum arm 9 and the pivot axis 10 of this arm 9. Furthermore, in as regards the clutch and disengagement device proper, only the roller 15 and the drive shaft 12 have been shown diagrammatically in FIG. 2.

This machine which makes it possible to produce self-twisted core wires has a plurality of identical working positions, placed side by side on a support frame.

In the upper part of the frame 20 is arranged a supply of wicks of fibers 8 to be treated. The processing members are constituted by a drawing assembly arranged vertically on this frame and a self-twisting system 35, constituted for example by a false twist spindle 36 and a member 37 making it possible to vary the length of the twist rise ( intermittent deliverer), is arranged immediately below the pair of stretching cylinders 6, 7. The two treated wires, after assembly by self-rotation are called up by means of a conventional deliverer 37 to then be returned to 38. The supply in core wire 11 is obtained by means of a deliverer 39, these wires coming from a creel 40 spaced from the frame and arranged opposite the latter.

Such an installation is equipped with means allowing the automatic disengagement of the drawing train of the wick in the event of breakage of the latter; these means are functionally connected on the one hand, to a wire cutter 41 for the core wire and to a detector 42 for controlling the winding.

In the case of breakage of the wick 8, the drawing train is disengaged in accordance with the example described in FIG. 1, but simultaneously, the cutting of the wire 41 and the stop of the winding at 42 are controlled. Similarly, if the core wire 11 breaks, the wire cutter 42 automatically triggers the disengaging of the drawing train.

During the restarting operation, the clutch is carried out as described above, this clutch being able to be produced progressively by varying the movements of the roller 15 relative to the motor shaft 12 and to the cylinder 2.

In normal operation, a positive clutch can possibly be produced as illustrated in the example illustrated in FIG. 4.

The stretching device according to the invention therefore guarantees great safety in the operation of the installations on which it is mounted.

Furthermore, compared with previous systems for individual disengaging of the stretching train, it also favors recovery operations by the fact that the stretching members can be pressurized before passing the wick and especially by the fact that it is possible to cause this clutch gradually, which is particularly advantageous in the case of a machine operating at high speed.

Of course, the invention is not limited to the embodiments described above, but it also covers all the variants produced in the same spirit. As already said, the clutch and declutching devices according to the invention can easily be coupled to a system allowing its intermittent control so as to obtain wires having effects on their length.

Claims (6)

1. Device for controlling a system for the drawing of at least one strand of fibres (8) in order to transform it in a spun yarn, said drawing system including one pair of feed rollers (1), (2), one pair of sleeves (3), (4) and one pair of drawing rollers (6), (7) with all of these elements, under normal operating conditions, being maintained under pressure by means of a swinging arm (9), which may be moved into and out of the operating position, the arm (9) holding one of the feed rollers (1), (2), one of the sleeves (3), (4), and one of the drawing rollers (6), (7), a control system being provided to start and stop each drawsystem of the equipment, characterized by the fact that the feed rollers (1), (2), at least when starting up, are driven by a friction clutch roller (15) connected to every operating position, said roller (15) being movable and coming, when engaged, into contact with both one of the feed rollers (2) and a driving shaft (12), which extends throughout and parallel to the length of the frame and which is spaced from such a driven feed roller (2), said system making possible, when starting up, a progressive clutch of the drawsystem.

2. Device according to the claim 1, characterized by the fact that the driving of the pair of drawing rollers is given by a spliced driving shaft (7), said shaft being common for all the operating positions, the drawing roller (6) held by the swinging arm (9) resting therein.

3. Device according to one of the claims 1 and 2, characterized by the fact that the sleeves (3), (4) are driven by the feed roller (2) by means of a belt (13) connecting this roller (2) to the shaft (14) bearing one of the sleeves (4).

4. Device according to one of the claims 1 to 3, characterized by the fact that the motion of the clutch roller (15) is operated by a lever system.

5. Device according to one of the claims 1 to 4, characterized by the fact that it comprises means allowing the self-release of the clutch roller, sais means being controlled either by a device for detecting if the roving break or by other safety devices, such as one for detecting if the yarn produced breaks.

6. Device according to one of the claims 1 to 4, characterized by the fact that the clutch roller (15) connected to every operating position is mounted on a support (34) allowing saif roller to be disengaged in the normal course of operation, and simultaneously changes the friction clutch system by a positive clutch system, such as for instance a pinion (135) which becomes engaged into a mating pinion (139) on the driving shaft (12).

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